let sz = 50;

let rinterval = 60;

let a = 0;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  x = width/2;

  y = height/2;

  smooth();

}

​

function draw() {

  background(0);

  if(frameCount%rinterval < 1) {

    x = random(sz, width);

    y = random(sz, height-sz);

    rinterval = random(30, 3000);

    a = 0;

    console.log("NEW", rinterval);

  }

  a += rinterval/255;

  fill(255, a);

  ellipse(x, y, sz, sz);

}